The present invention relates to a system and method for making and inspecting of multi-component wrapped articles; more specifically, to a system and a method for the optical inspection, registration, and rejection of cigarettes on an open garniture combiner.
A well-known filter cigarette 21 structure is shown in FIG. 1. A rod 23 of tobacco is manufactured on a commercially available cigarette machine; e.g. those manufactured by Molins PLC, and others. The tobacco rod 23 is, in its simplest form, a column of cut tobacco filler 25 wrapped in a paper wrapper 27 held in place by a longitudinal adhesive seam 29. A filter 31 included with the cigarette 21 is manufactured by gathering a length of cellulose acetate, treating the cellulose acetate and forming a cylindrical filter element or plug 33, and encasing the filter element in xe2x80x9cplug wrapxe2x80x9d 35.
As seen in FIG. 2, in a typical manufacturing process for the tobacco rod 23, the paper wrapper 27 in the form of a continuous web is moved at high speed in the direction of arrow 37, herein referred to as the wrapping direction, toward a so-called garniture section 39 of a cigarette making machine. The tobacco filler 25 is deposited on the wrapper 27 prior to the garniture section 39. The garniture section 39 typically includes a first end 41 that is flat or slightly curved and upwardly open, a second end 43 in the form of a sleeve with a hole equal to the diameter of the cigarette 21, and a curved surface 45 connecting the first and second ends. The garniture section 39 is designed to curl the moving paper wrapper 27 around the tobacco rod 23, i.e., in a direction transverse to the wrapping direction 37 as the wrapper moves in the wrapping direction. Preferably, before encountering the garniture section 39, the wrapping paper 27 is already curling upwards to fit against the inner surface 45 of the garniture section. Closure of the wrapper 27 around the tobacco filler 25 to form the rod 23 occurs at the exit 43 of the garniture section 39 where the rod exits through the hole. The continuous rod 23 is subsequently cut at some downstream point C to form a tobacco rod 23 of a desired length.
There are numerous methods known for joining the cut tobacco rod 23 to the filter 31. As seen in FIG. 3, a common method of joining the rod 23 and the filter 31 involves xe2x80x9ctippingxe2x80x9d a double-length rod of tobacco 23 with filters 31 adjacent to both ends of the rod and cutting the rod in half to yield two filter cigarettes. The filters 31 are connected to the tobacco rod 23 by an overwrap of paper 47 called xe2x80x9ctipping paperxe2x80x9d. Generally, the handling of the filters 31, cut tobacco rods 23, and finished cigarette 21 during the combining step is handled by vacuum rollers (not shown). The components fit into flutes on the outside periphery of the rollers and are held in place by an applied vacuum force as they are moved from place to place.
The final products are given an exterior inspection, such as discussed in U.S. Pat. Nos. 5,235,649, 5,366,096, 5,414,270, 5,013,905 and 4,976,544. Such prior art inspections involve optical inspection with a video camera. The image is fed into a digital computer; then the image is analyzed for the presence of defects. Other inspections, such as density inspections, may also be made by exposing the cigarette or rod to various forms of electromagnetic radiation, such as in U.S. Pat. Nos. 5,010,904, 4,001,579, 4,986,285 and 4,212,541. The prior art inspection systems are not typically concerned with relative placement of internal components of the cigarette, because the tobacco rod 23 and the filter 31 typically abut.
The development of new types of cigarettes, such as those in U.S. Pat. No. 5,388,594 which has multiple internal components disposed at precise distances from one another, requires the development of new inspection systems. Cigarettes according to the ""594 patent contain a tobacco plug, a hollow void chamber, a hollow acetate tube, and a filter. The relative positioning of the interior components of these cigarettes is crucial to their proper operation and must be carefully maintained. It may happen that, in the manufacturing of such cigarettes, machine settings will require adjustment to maintain consistent placement of components.
Visual inspection of the final product to determine the relative placement of components is impossible according to the prior art inspection systems without manually disassembling the finished cigarette due to the various layers paper or other material surrounding the components. Such disassembly would likely disturb the interior spacing and would, in any event, occur too late in the manufacturing process to provide useful feedback for correcting machine settings in a timely manner.
The present invention provides a solution to the problem of ensuring that the intended structure of multi-component cigarettes is maintained within design specifications by providing for optical inspection of the multi-component cigarette, preferably within a garniture section prior to closure of a wrapping paper. The present invention also permits providing for the rejection of cigarettes that do not meet specified requirements.
In accordance with one aspect of the present invention, an apparatus for making and inspecting a multi-component cigarettes, each cigarette including two or more different components arranged relative to one another, is provided. The apparatus includes a device for advancing a web in a first direction. The apparatus further includes a device for positioning at least two different components of a cigarette relative to one another on the web as the web advances in the first direction. The apparatus further includes a garniture device for wrapping the web around the at least two different components by moving opposite edges of the web transversely to the first direction such that, at a closure point in the garniture device, the opposite edges overlap each other. The apparatus further includes an imaging device disposed upstream of the closure point for generating an image of the at least two different components. The apparatus further includes a processing device connected to the imaging device for comparing the generated image with a reference standard and determining if the generated image deviates from the reference standard.
In accordance with another aspect of the present invention, an apparatus for making and inspecting a multi-component articles, each article including two or more components arranged relative to one another, is provided. The apparatus includes a device for arranging two or more components of a multi-component article relative to one another. The apparatus further includes an imaging device arranged relative to the arranging device for generating an image of the components of the multi-component articles. The apparatus further includes a processing device connected to the imaging device for comparing the generated image with a reference standard and determining if the generated image deviates from the reference standard.
In accordance with another aspect of the present invention, a method for making and inspecting a multi-component cigarettes, each cigarette including two or more different components arranged relative to one another, is provided. According to the method, a web is advanced in a first direction, and at least two different components of a cigarette are positioned relative to one another on the web as the web advances in the first direction. The web is wrapped around the at least two different components by moving opposite edges of the web transversely to the first direction with a garniture device such that, at a closure point in the garniture device, the opposite edges overlap each other. An image of the at least two different components is generated with an imaging device disposed upstream of the closure point. The generated image is compared with a reference standard and it is determined if the generated image deviates from the reference standard with a processing device.
According to still another aspect of the present invention, a method of making and inspecting a multi-component article is disclosed. According to the method, a plurality of components are arranged relative to one another. An image of the arranged components is generated with an imaging device. The generated image is compared with a reference standard. It is determined if the generated image deviates from the reference standard.